1. Field of the Invention
The present invention relates to a functional photoelectric device utilizing a superconducting transition temperature enhancement effect caused by a light irradiation thereto. More particularly, it relates to a superconducting photoelectric device which can be employed as a high speed light switch device, a photo detector or a light memory device.
2. Description of the Related Arts
In recent years, higher speed computer systems have required higher speed switching devices and memory devices have been required. As a high speed device to meet these requirements, there has been developed a superconductive transistor employing a Josephson junction. Switching operation of this transistor is carried out by electrically injecting electrons or positive holes into a semiconductor region located between superconductive regions. Accordingly, it takes some time for the electrons or the positive holes to be injected thereto, resulting in a limit of its speed. Moreover, there has been proposed a superconductive photo-transistor which switches between its superconductive state and its normally conducting state in response to light irradiation, such as disclosed in Japanese Unexamined Patent Publication 64-65884 or 63-239877. However, there has never been accomplished yet a superconductive device which switches from a normally conducting state to a superconductive state in response to a light irradiation. This is logically reverse to that of the prior art device.